U.S. patent application number 12/339221 was filed with the patent office on 2009-11-26 for gas delivery system for an ion source.
This patent application is currently assigned to VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.. Invention is credited to Chris CAMPBELL, Stefan CASEY, Kevin M. KEEN, Robert LINDBERG, John SLOCUM.
Application Number | 20090289197 12/339221 |
Document ID | / |
Family ID | 40853372 |
Filed Date | 2009-11-26 |
United States Patent
Application |
20090289197 |
Kind Code |
A1 |
SLOCUM; John ; et
al. |
November 26, 2009 |
GAS DELIVERY SYSTEM FOR AN ION SOURCE
Abstract
An ion source has an arc chamber with an electron-emitting
element and a repeller. A manifold assembly defines a cavity and a
gas outlet configured to allow gas flow to the arc chamber. This
gas outlet is closer to the repeller than the electron-emitting
element. In one embodiment, the ion source has a first crucible and
a second crucible. The first crucible and the second crucible are
connected to the manifold assembly. In one instance, the crucibles
have tamper-resistant features.
Inventors: |
SLOCUM; John; (Medford,
MA) ; KEEN; Kevin M.; (Medford, MA) ;
CAMPBELL; Chris; (Newburyport, MA) ; LINDBERG;
Robert; (Rockport, MA) ; CASEY; Stefan;
(Clifton Park, NY) |
Correspondence
Address: |
VARIAN SEMICONDUCTOR EQUIPMENT ASSC., INC.
35 DORY RD.
GLOUCESTER
MA
01930-2297
US
|
Assignee: |
VARIAN SEMICONDUCTOR EQUIPMENT
ASSOCIATES, INC.
Gloucester
MA
|
Family ID: |
40853372 |
Appl. No.: |
12/339221 |
Filed: |
December 19, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61018690 |
Jan 3, 2008 |
|
|
|
Current U.S.
Class: |
250/424 ;
250/426 |
Current CPC
Class: |
H01J 2237/006 20130101;
H01J 27/08 20130101; H01J 37/3171 20130101; H01J 2237/082 20130101;
H01J 2237/061 20130101; H01J 37/08 20130101 |
Class at
Publication: |
250/424 ;
250/426 |
International
Class: |
H01J 27/00 20060101
H01J027/00 |
Claims
1. An ion source comprising: an arc chamber having an
electron-emitting element and a repeller; and a manifold assembly
defining a cavity and a gas outlet, said gas outlet configured to
allow gas flow to said arc chamber, said gas outlet being closer to
said repeller than said electron-emitting element.
2. The ion source of claim 1, wherein said electron-emitting
element is an indirectly heated cathode.
3. The ion source of claim 1, further comprising a first crucible
and a second crucible, said first crucible and said second crucible
connected to said manifold assembly.
4. The ion source of claim 3, wherein each of said first crucible
and said second crucible has a tamper-resistance means.
5. The ion source of claim 3, further comprising a wall at least
partially disposed between said first crucible and said second
crucible.
6. The ion source of claim 5, further comprising a cooling
mechanism, wherein said cooling mechanism is configured to cool
said wall.
7. The ion source of claim 6, wherein said wall defines a fluid
passage and wherein said cooling mechanism provides a fluid to said
fluid passage.
8. The ion source of claim 3, further comprising a lamp configured
to heat at least one of said first crucible and said second
crucible.
9. The ion source of claim 1, wherein said gas outlet is
approximately 25% a distance between said electron-emitting element
and said repeller.
10. The ion source of claim 1, wherein said gas outlet is less than
approximately one inch from said repeller.
11. The ion source of claim 1, wherein said gas outlet is less than
2.5 inches from said repeller.
12. A method comprising: providing an arc chamber with an
electron-emitting element and a repeller and providing a gas outlet
configured to allow gas flow to said arc chamber; flowing a gas
into said arc chamber closer to said repeller than said
electron-emitting element; and ionizing said gas in said arc
chamber.
13. A crucible comprising: a canister defining a cavity; a crucible
cap connected to said canister, said crucible cap defining an
aperture and at least one hole; a nozzle disposed in said aperture
of said crucible cap, said nozzle having a rim inside said cavity
disposed on said crucible cap configured to prevent said nozzle
from being withdrawn through said aperture; and at least one pin
disposed in said hole of said crucible cap, said pin configured to
secure said crucible cap to said canister.
14. The crucible of claim 13, wherein said crucible further
comprises a plug disposed on said nozzle opposite said rim, said
plug composed of vinyl.
15. The crucible of claim 13, wherein said crucible further
comprises a shipping cap disposed over said nozzle.
16. The crucible of claim 13, wherein said nozzle is selected from
the group consisting of tungsten and stainless steel.
17. The crucible of claim 13, wherein said pin is stainless
steel.
18. The crucible of claim 13, wherein said crucible cap has threads
for engagement with said canister.
19. The crucible of claim 13, wherein said nozzle has threads for
engagement with said crucible cap.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to the provisional patent
application entitled "Carborane Delivery System," filed Jan. 3,
2008 and assigned U.S. App. No. 61/018,690, the disclosure of which
is hereby incorporated by reference.
FIELD
[0002] This disclosure relates to ion sources, and more
particularly to an ion source for large molecular compounds.
BACKGROUND
[0003] Ion implantation is a standard technique for introducing
conductivity-altering impurities into workpieces, such as
semiconductor wafers. A desired impurity material is ionized in an
ion source of an ion implanter, the ions are accelerated to form an
ion beam of prescribed energy, and the ion beam is directed at the
surface of the workpiece. The energetic ions in the beam penetrate
into the bulk of the semiconductor material and are embedded into
the crystalline lattice of the semiconductor material in the
workpiece to form a region of desired conductivity.
[0004] An ion source is a critical component of an ion implanter.
The ion source is required to generate a stable, well-defined ion
beam for a variety of different ion species and extraction
voltages. Electrons generated by the ion source will ionize a
dopant gas to produce a plasma. This plasma may be formed into the
ion beam used for implantation.
[0005] Large molecular compounds have been previously used in ion
implanters. Carborane C.sub.2B.sub.10H.sub.12 is one example of a
large molecular compound that may be used in ion implantation.
Implantation of large molecular ions allows the equivalent of a
high current, low energy atomic dopant ion implant with reduced
energy contamination. Large molecules, such as
C.sub.2B.sub.10H.sub.12, may have multiple dopant atoms per
molecule. To obtain a specific dose, fewer large molecules are
required than dopant atoms because each molecule may have multiple
dopant atoms. Thus, for large molecules the dose or beam current
may be reduced to attain a similar dose of dopant atoms or the dose
may be increased at a particular beam current compared to that beam
current of dopant atoms. Large molecule ions may obtain a similar
depth as a dopant atom ion with higher energy due to the large
molecule's size. This larger size may prevent channeling, or
implantation substantially between the atoms of the crystal lattice
of the workpiece. Thus, the beam energy may be increased for large
molecule ions compared to dopant atom ions to obtain a similar
implant depth. These higher beam energies reduce energy
contamination in the beam and may limit the space-charge
effect.
[0006] C.sub.2B.sub.10H.sub.12 and other large molecules present
particular design challenges in an ion source. First, a large time
between refills of a crucible, or recharge interval, in the ion
source is desirable. C.sub.2B.sub.10H.sub.12 and other large
molecules require a large reservoir of powder that is vaporized or
sublimed to produce the vapor used in the ion source. A
standard-sized crucible may not hold enough material to operate for
long periods of time between recharges. Second, wall reactions may
occur when material from the crucible condenses on a contacted
surface. A material, such as C.sub.2B.sub.10H.sub.12 or another
large molecule, may condense on non-heated surfaces. This
condensation may lead to clogging or buildup on surfaces within the
gas delivery system or the arc chamber. Third, pyrolysis may occur
in an ion source. Pyrolysis is the decomposition of a compound or
molecule by heating. Organic substances are one example of a
compound or molecule that may decompose due to pyrolysis. The heat
within a standard ion source may cause large molecules, such as
C.sub.2B.sub.10H.sub.12, to break up or decompose. Lastly, it is
difficult to switch species or have two crucibles with two
different species operating in one ion source. In many designs,
heat from operating one crucible to vaporize one species, such as
arsenic, also may unintentionally vaporize the
C.sub.2B.sub.10H.sub.12 or other large molecules in another
crucible.
[0007] Accordingly, there is a need for a apparatus for ionization
of large molecules in an ion implanter which overcomes the
above-described inadequacies and shortcomings.
SUMMARY
[0008] According to a first aspect of the invention, an ion source
is provided. The ion source comprises an arc chamber and a manifold
assembly. The arc chamber has an electron-emitting element and a
repeller. The manifold assembly defines a cavity and a gas outlet,
the gas outlet configured to allow gas flow to the arc chamber. The
gas outlet is closer to the repeller than the electron-emitting
element.
[0009] According to a second aspect of the invention, a method is
provided. The method comprises providing an arc chamber with an
electron-emitting element and a repeller and providing a gas outlet
configured to allow gas flow to the arc chamber. A gas is flowed
into the arc chamber closer to the repeller than the
electron-emitting element. The gas is ionized in the arc
chamber.
[0010] According to a third aspect of the invention, a crucible is
provided. The crucible comprises a canister defining a cavity. A
crucible cap is connected to the canister, the crucible cap
defining an aperture and at least one hole. A nozzle is disposed in
the aperture of the crucible cap, the nozzle having a rim inside
the cavity disposed on the crucible cap configured to prevent the
nozzle from being withdrawn through the aperture. At least one pin
is disposed in the hole of the crucible cap, the pin configured to
secure the crucible cap to the canister.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a better understanding of the present disclosure,
reference is made to the accompanying drawings, which are
incorporated herein by reference and in which:
[0012] FIG. 1 is a simplified block diagram of a beam-line ion
implanter;
[0013] FIG. 2 is cross-sectional view of an embodiment of an ion
source for use in an ion implanter;
[0014] FIG. 3 is an exploded perspective view of one side of an
embodiment of a manifold for use in the vaporizer assembly of FIG.
2;
[0015] FIG. 4 is a perspective view of the other side of an
embodiment of a manifold for use in the vaporizer assembly of FIG.
2;
[0016] FIG. 5 is a cross-sectional view of a first embodiment of a
crucible with tamper-resistant features; and
[0017] FIG. 6 is a cross-sectional view of a second embodiment of a
crucible with tamper-resistant features.
DETAILED DESCRIPTION
[0018] FIG. 1 is a simplified block diagram of a beam-line ion
implanter. Those skilled in the art will recognize that the
beamline ion implanter 200 is only one of many examples of
differing beamline ion implanters. Embodiments of this apparatus
also may be applicable to other ion implantation systems or other
workpiece or semiconductor wafer processing equipment. In general,
the beamline ion implanter 200 includes an ion source 280 to
generate ions that are extracted to form an ion beam 281, which may
be, for example, a ribbon beam or a spot beam. The ion beam 281 may
be mass analyzed and converted from a diverging ion beam to a
ribbon ion beam with substantially parallel ion trajectories in one
instance. The beamline ion implanter 200 may further include an
acceleration or deceleration unit 290 in some embodiments.
[0019] An end station 211 supports one or more workpieces, such as
workpiece 138, in the path of the ion beam 281 such that ions of
the desired species are implanted into workpiece 138. In one
instance, the workpiece 138 may be a semiconductor wafer having a
disk shape, such as, in one embodiment, a 300 mm diameter silicon
wafer. However, the workpiece 138 is not limited to a silicon
wafer. The workpiece 138 could also be, for example, a flat panel,
solar, or polymer substrate. The end station 211 may include a
platen 295 to support the workpiece 138. The end station 211 also
may include a scanner (not shown) for moving the workpiece 138
perpendicular to the long dimension of the ion beam 281
cross-section, thereby distributing ions over the entire surface of
workpiece 138.
[0020] The ion implanter 200 may include additional components
known to those skilled in the art such as automated workpiece
handling equipment, Faraday sensors, or an electron flood gun. It
will be understood to those skilled in the art that the entire path
traversed by the ion beam is evacuated during ion implantation. The
beamline ion implanter 200 may incorporate hot or cold implantation
of ions in some embodiments.
[0021] FIG. 2 is cross-sectional view of an embodiment of an ion
source for use in an ion implanter. Ion source 310, which may
correspond to or be part of the ion source 280 of FIG. 1 in one
particular embodiment, includes a vaporizer assembly 312. The
vaporizer assembly 312 includes at least two crucibles: first
crucible 300 and second crucible 301. In other embodiments, one
crucible or more than two crucibles are included. These crucibles
are configured to vaporize or sublime large molecules, such as
C.sub.2B.sub.10H.sub.12, into a vapor. In another instance, these
crucibles also may be configured to vaporize or sublime other
compounds such as, for example, boron-containing,
arsenic-containing, or phosphorus-containing compounds. This
vaporization may be performed by heating the crucibles with
tungsten filament lamps 314, 315. The tungsten filament lamps 314,
315 in one instance operate at approximately 500 W to heat the
first crucible 300 and second crucible 301. In this particular
embodiment, the lamps 314, 315 are positioned near the side of the
first crucible 300 and second crucible 301, but other locations,
such as below the first crucible 300 and second crucible 301, are
possible. Other heating methods known to those skilled in the art,
such as a resistive coil heater, also may be used. The crucibles
300, 301 vary in size as is known to those skilled in the art and
each may have its temperature monitored with a temperature
probe.
[0022] The first crucible 300 includes a nozzle 302 and the second
crucible 301 includes a nozzle 303. Both the nozzle 302 and nozzle
303 lead to the cavity 305 of the manifold assembly 304. The cavity
305 may be considered a manifold in one instance. The first
crucible 300 and second crucible 301 may be coupled to the manifold
assembly 304 using the nozzle 302 and nozzle 303. In other
embodiments, the first crucible 300 and second crucible 301 may be
screwed or otherwise disposed onto other parts of vaporizer
assembly 312. In one particular instance, the nozzle 302 and nozzle
303 slide into the manifold assembly 304. A close fit or low
clearance between the nozzle 302 or nozzle 303 and the manifold
assembly 304 may reduce leakage and allow heat transfer from the
arc chamber 306 or the manifold assembly 304 to the nozzle 302,
nozzle 303, first crucible 300, or second crucible 301. This heat
transfer may, for example, heat the nozzle 302 or nozzle 303 such
that condensation of a vapor is prevented or reduced. This may
prevent or reduce clogging of the nozzle 302 or nozzle 303 with any
condensed vapor.
[0023] A pressure difference between the first crucible 300 and
second crucible 301 and the arc chamber 306 means that vapor may
only flow to the arc chamber 306. The arc chamber 306 may be at a
lower pressure than the crucibles 300, 301. This design of the ion
source 310 where material will flow into the arc chamber 306 due to
the pressure difference is configured to prevent leakage from the
crucibles 300 and 301 and, in turn, prevents material from the
crucibles 300 and 301 from condensing on any contacted surface.
Thus, any condensation on walls within the manifold assembly 304 or
nozzles 302, 303 that form difficult-to-clean deposits are
minimized.
[0024] The manifold assembly 304 allows either the first crucible
300 or the second crucible 301 to operate individually. The
manifold assembly 304 also allows both the first crucible 300 and
the second crucible 301 to operate together. In an embodiment where
C.sub.2B.sub.10H.sub.12 or another large molecule is used in both
the first crucible 300 and the second crucible 301, this doubles
the total available charge to the ion source 310.
[0025] The manifold assembly 304 has a gas outlet 313 that is
linked with an arc chamber 306. The arc chamber 306 has an
electron-emitting element. The electron-emitting element in this
particular embodiment is an indirectly heated cathode 307 with a
filament 308 and a repeller 309. In operation, the filament 308
will heat the indirectly heated cathode 307. The indirectly heated
cathode 307 emits electrons into the arc chamber 306 which are at
least partly repelled by the repeller 309. Large molecules, such as
C.sub.2B.sub.10H.sub.12, or other arsenic-containing compounds,
phosphorus-containing compounds, boron-containing compounds, or
other compounds are ionized within the arc chamber 306 using these
electrons. Other electron-emitting elements, such as filaments or
Bernas sources may be used in other embodiments. Other ion sources,
such as microwave, electron gun, or other ion sources known to
those skilled in the art, also may be used in other embodiments. In
yet another embodiment, two or more different plasma generating
sources ("dual mode") are linked within the arc chamber 306 to
ionize the various compounds. One particular instance may include,
for example, an indirectly heated cathode and a microwave ion
source.
[0026] The gas outlet 313 of the manifold assembly 304 directs the
vapor from the first crucible 300 or second crucible 301 to a
region of the arc chamber 306 farther from the electron-emitting
element than the repeller 309. This reduces the occurrence of
pyrolysis of the vapor in the arc chamber 306. Pyrolysis is the
decomposition of a compound or molecule by heating, such as an
organic molecule.
[0027] In this particular embodiment, the gas outlet 313 is
disposed closer to the repeller 309 than the indirectly heated
cathode 307. In one particular embodiment, the gas outlet 313 is
located approximately 2.5 inches from the indirectly heated cathode
307. In another particular embodiment, the gas outlet 313 is
located approximately 0.89 inches from the repeller 309 and
approximately 2.71 inches from the indirectly heated cathode 307.
In yet another particular embodiment, the gas outlet 313 is located
approximately 25% the distance between the repeller 309 and the
indirectly heated cathode 307 with the gas outlet 313 closer to the
repeller 309 than the indirectly heated cathode 307. In other
embodiments, the gas outlet 313 is located less than approximately
2.5 inches from said repeller or less than approximately 1 inch
from said repeller.
[0028] C.sub.2B.sub.10H.sub.12, which is merely one example of a
large molecule, will break up at approximately 700.degree. C. The
indirectly heated cathode 307 may operate as high as approximately
2000.degree. C. Therefore, moving the gas outlet 313 away from the
indirectly heated cathode 307 reduces pyrolysis of
C.sub.2B.sub.10H.sub.12.
[0029] The manifold assembly 304 contacts the arc chamber 306 in
this embodiment, which will allow heat transfer from the arc
chamber 306 to the manifold assembly 304. This will prevent the
vapor in the cavity 305 of the manifold assembly 304 from cooling
and condensing on surfaces of the manifold assembly 304. Preventing
this condensation may prevent clogging or buildups within the
manifold assembly 304. The manifold assembly 304 may have
insulation in one embodiment to at least partly limit the amount of
heat transfer to the manifold assembly 304 from the arc chamber
306.
[0030] A cooled separator wall 311 may be disposed between the
first crucible 300 and the second crucible 301. The cooled
separator wall 311 defines a fluid passage 317. This fluid passage
317 allows passage of a fluid, such as water, supplied by the
cooling mechanism 316. The fluid will allow the temperature of the
cooled separator wall 311 to be controlled. The cooling mechanism
316 may be part of a cooling system for an ion implanter 200 in one
instance.
[0031] This cooled separator wall 311 is configured to allow one of
the two crucibles to run at a vaporization temperature during
certain times while preventing heat transfer to the other crucible
or keeping the other crucible at a lower temperature. Thus, in this
instance only one of the two crucibles will vaporize any material
located within it. The cooled separator wall 311 also prevents
"cross-talk" between the two crucibles. By preventing "cross-talk,"
material in one crucible at a lower temperature is not vaporized
into the cavity 305 due to the operation of the other crucible at
the higher temperature.
[0032] The cooled separator wall 311 may allow one of the crucibles
300, 301 to vaporize or sublime a large molecule, such as
C.sub.2B.sub.10H.sub.12. In this instance, only one of the
crucibles may be operating at a time. The cooled separator wall 311
prevents the large molecule in the one crucible from being
vaporized or sublimed by the operation of the other crucible.
[0033] The cooled separator wall 311 also may be used to allow
different implant species to be used. For example, in one
embodiment C.sub.2B.sub.10H.sub.12 is located in the first crucible
300 while an arsenic-containing compound is located in the second
crucible 301. The cooled separator wall 311 allows for the
operation of the second crucible 301 without unintentionally
vaporizing the C.sub.2B.sub.10H.sub.12 in the first crucible
300.
[0034] In an alternate embodiment, the manifold assembly 304 is
connected to gas sources rather than crucibles 300, 301. Thus, the
ion source 310 is not merely limited to vaporization or sublimation
of a material in a crucible and may operate by flowing at least one
gas into the manifold assembly 304.
[0035] FIG. 3 is an exploded perspective view of one side of an
embodiment of a manifold for use in the vaporizer assembly of FIG.
2. The surface 318 faces the crucibles 300, 301 of FIG. 2. The
manifold insert 400 is disposed on the manifold assembly 304 and at
least partially covers the cavity 305. Again, the manifold assembly
304 includes a single gas outlet 313. The manifold insert 400 in
this particular embodiment is removable from the manifold assembly
304. This manifold insert 400 further includes nozzle holes 401 and
402 in this embodiment. More or fewer nozzle holes may be included
in the manifold insert 400. The nozzle holes 401 and 402 are
configured to be disposed closely with any nozzles, such as nozzle
302 and nozzle 303 of FIG. 2. This close fitting helps prevent
backflow or leakage of vaporized material as it leaves the nozzles
302, 303. In one particular embodiment, the manifold insert 400 has
nozzle holes 401 and 402 that are configured to be necked down or
to have a varying diameter along the length of the nozzle holes
401, 402. This may help prevent backflow.
[0036] FIG. 4 is a perspective view of the other side of an
embodiment of a manifold for use in the vaporizer assembly of FIG.
2. The surface 319 faces the arc chamber 306 of FIG. 2. As seen in
FIG. 4, the manifold assembly 304 is configured in a manner
consistent with FIG. 2. While the manifold assembly 304 allows
materials vaporized within multiple crucibles to be transported
through cavity 305, it includes a single gas outlet 313.
[0037] FIG. 5 is a cross-sectional view of a first embodiment of a
crucible with tamper-resistant features. The crucible 300 includes
a canister 500 with threaded portion 504 around the circumference
of the canister 500. A crucible cap 502 may be screwed onto this
threaded portion 504 of the canister 500. However, any method known
to a person skilled in the art that disposes the crucible cap 502
on the canister 500 may be used. Thus, the crucible 300 is not
limited solely to use of the threaded portion 504. The canister 500
and crucible cap 502 may be, for example, graphite. This canister
500 is configured to hold C.sub.2B.sub.10H.sub.12 or other large
molecules, for example, but may also hold other compounds or
species known to those skilled in the all.
[0038] A nozzle 302 is inserted into the crucible cap 502. This
nozzle 302 may be, for example, tungsten or stainless steel. In one
instance, the nozzle 302 is screwed into the crucible cap 502. The
nozzle 302 is flanged at the bottom to form a rim 507 that prevents
removal of the nozzle 302 from the crucible cap 502. The nozzle 302
may only be removed through screwing or pushing the nozzle 302 into
the canister 500 or by breaking the crucible cap 502 or nozzle 302.
Thus, removal of the nozzle 302 is prevented.
[0039] A shipping cap 503 is disposed on top of the crucible 300.
The shipping cap 503 may be screwed onto, snapped onto, or
otherwise disposed on the canister 500 or crucible cap 502. Any
method that connects the shipping cap 503 to the canister 500 or
crucible cap 502 known to those skilled in the art may be used.
This shipping cap 503 may be removed before insertion into any ion
source, such as ion source 310 of FIG. 2.
[0040] The crucible 300 further includes two pins 505 and 506. In
one instance, the pins 505 and 506 are stainless steel. These pins
are inserted through the crucible cap 502 into the canister 500 of
the crucible 300. In this particular embodiment, the pins 505 and
506 are located under the threaded portion 504, but the pins 505
and 506 may be placed elsewhere in the crucible cap in other
embodiments as is known to those skilled in the art. Other
embodiments may use more or less than two pins and the crucible 300
is not solely limited to having two pins. The pins 505 and 506 may
be separate from and inserted through the crucible cap 502 or may
be assembled as part of the crucible cap 502 to be pushed into the
canister 500 to make it tamper-resistant.
[0041] The pins 505 and 506 are configured to lock the crucible cap
502 on the canister 500. The pins 505 and 506 in some embodiments
are configured to be permanently affixed within the crucible cap
502 and the canister 500. While a user may be able to unscrew the
crucible cap 502 to a certain extent in some embodiments, the
crucible cap 502 cannot be fully removed from the canister 500
without breaking the crucible cap 502 and/or canister 500 due to
the presence of the pins 505 and 506. This makes the crucible cap
502 resistant to tampering and may assure the quality of the
compound within the crucible 300.
[0042] FIG. 6 is a cross-sectional view of a second embodiment of a
crucible with tamper-resistant features. This particular embodiment
does not include a shipping cap 503. Instead, a plug 601 is
disposed on the top of the nozzle 302. In some embodiments, the
plug 601 may be rubber, vinyl, or a polymer and may be slipped on
and off the nozzle 302.
[0043] The present disclosure is not to be limited in scope by the
specific embodiments described herein. Indeed, other various
embodiments of and modifications to the present disclosure, in
addition to those described herein, will be apparent to those of
ordinary skill in the art from the foregoing description and
accompanying drawings. Thus, such other embodiments and
modifications are intended to fall within the scope of the present
disclosure. Furthermore, although the present disclosure has been
described herein in the context of a particular implementation in a
particular environment for a particular purpose, those of ordinary
skill in the art will recognize that its usefulness is not limited
thereto and that the present disclosure may be beneficially
implemented in any number of environments for any number of
purposes. Accordingly, the claims set forth below should be
construed in view of the full breadth and spirit of the present
disclosure as described herein.
* * * * *